1. Field of the Invention
Shelves in food stores are stocked with containers for liquid, shortening, lard, shelled peanuts, granular or freeze-dried or instant coffee, bread crumbs, powdered milk, salt and other granular, coarse, as well as flake particles used by consumers, subject to resealing or repeated opening and closing of the container. Such containers include a body of composite structure including a molded plastic closure adhesively attached thereto and usually having a plastic over-closure or flexible lid to reseal the container or package after opening thereof, including those subject to resealing or repeated opening and closing of the container.
2. Description of the Prior Art
U.S. Pat. No. 4,030,630--Yearly dated June 21, 1977 provides an all plastic reclosable container presently found in some food stores and having a lid with a disc-shaped flat-panel central section and a peripheral crescent-shaped or spiral tear strip pushable and/or pullable to allow opening thereof along a first score line that surrounds the flat panel section and a second score line that merges with the first at a particular location and then follow a path essentially concentric to the circumferential score for approximately 180 degrees of arc. This forms a tear strip that allows the container to be opened by pressing down on an end of the tear strip near the location where the score lines merge to rupture the scoring at the end of the tear strip. A finger can then enter the container to grasp the end of the tear strip and lift upward, tearing along the two score lines until an end of the secondary score is reached, and then following along the remainder of the circumferential score line until the panel of the closure is completely removed. The closure of this type has some potential drawbacks including: (a) the force required for the initial rupture at the end of the tear strip is relatively high, due to the lack of an effective concentration of stress at a particular point along the score lines; (b) to grasp the end of the tear strip after initial rupture, the finger must enter the container, which may be objectionable with certain container contents; (c) as the closure panel is completely torn away, the tear strip is in a position to act as a spring and, if the container held liquid or powdery contents, then any liquid or powdery contents remaining on the bottom of the closure panel could be flicked on the person opening the package; (d) the position of the secondary score line can cause molding problems if the closure cavity of the mold is center gated as desirable for multi-cavity molds designed for high production rates. Optionally, U.S. Pat. No. 4,030,630 discloses an upwardly-extending cantilever-projecting tab element used to aid the removal of the closure panel similar to a lift tab of an expired U.S. Pat. No. 2,383,274--Punte dated Aug. 21, 1945. U.S. Pat. No. 3,434,620--Laurizio dated Mar. 25, 1969 shows an annular finger loop to aid in lifting a frangible plastic closure. U.S. Pat. No. 4,331,256--Helms dated May 25, 1982 has a dispensing arrangement for a composite plastic and paperboard lid with a relatively thin paperboard central panel and an annular molded plastic rim including an arrow-shaped tab pivotally mounted on a bar for forcing a portion of the paperboard away from the plastic rim to provide a dispensing opening. U.S. Pat. No. 4,256,239--Yamaguchi et al dated Mar. 17, 1981 provides a pair of tongue-shaped strips to define a stress-concentrated point upon a thinned portion therebetween that is first sheared off. U.S. Pat. No. 3,863,801--Pillnik dated Feb. 4, 1975 has a camber and stress tab handle portion which will not rise above a top portion of a double seam of a can end closure. A popcorn package of expired U.S. Pat. No. 3,144,194--Cartwright dated Aug. 11, 1964 has a pan-shaped receptacle and a cover panel provided with circular cut score lines spaced from each other to define a tab adapted to be pressed and lifted for access to package contents. Expired U.S. Pat. No. 3,245,576--Griese has a container cover with a radially upwardly projecting tab along an edge thereof. A foreign Swedish Pat. No. 203,587--Andrea et al published Apr. 19, 1966 has a metal can lid with a radially pointed and embossed arrow tab member pivotable upwardly for access to can contents. U.S. Pat. No. Des. 248,376--Allen et al dated July 4, 1978 shows a flanged closure with a tear strip, and other prior art exists having rib disc closures and tear strips including U.S. Pat. Nos. 4,066,181--Robinson et al dated Jan. 3, 1978; 4,066,182--Allen et al dated Jan. 3, 1978; Des. 248,216--Allen et al dated June 20, 1978; Des. 248,217--Allen et al dated June 20, 1978; Des. 248,373--Allen dated July 4, 1978; 4,117,950--Allen dated Oct. 3, 1978; as well as U.S. Pat. Nos. 4,128,385--Allen dated Dec. 5, 1978 for a cross-gating apparatus and 4,128,613--Allen dated Dec. 5, 1978 for a cross-gating method.